Validation of the names of some species of Zygosphaera KAMPTNER
by Berit Riddervold Heimdal
It has been brought to my attention by Dr. R. E. Norris thatthe genus name Laminolithus which was proposed in HEIMDAL &GAARDER (1980) is a synonym of Zygosphaera KAMPTNER andinvalid under ICBN Art. 52. Therefore, the diagnosis ofZygosphaera_is emended,and the genus name Calyptrolithina
is proposed for ~- divergens HALLDAL & MARKALI which shows
characters excluding it from the emended Zygosphaera.
Zygosphaera KAMPTNER emend. HEIMDALKAMPTNER 1936, p. 244.
Diagnosis
Coccolith case subspherical, dimorphic. Solidly constructeddisc-shaped coccoliths (laminoliths} of regular calcite
rhombohedrons placed in layers parallel to coccolith bottom,with or without perforations approximately normal to bottom,
sides slightly tapering conically towards proximal end. Distal
surface of ordinary coccoliths usually flat with central knob
or thin ridge of microcrystals. Stomatal coccoliths (zygoform laminoliths) with high transverse, pointed ridge, withor without perforations.
Type: Zygosphaera hellenica KAMPTNER (SD: LOEBLICH & TAPPAN
1963, p. 194).
Testa coccolithica subsphaerica, dimorpha. Coccolithi "(laminolithi} discoformes solide constructi rhombohedris calcitis
regularibus laminis fundo coccolithico parallelis positis, cum
vel sine perforationibus fere fundo normalibus, lateribus
conice se ad finem proximalem modice minuentibus. Superficies
distans coccolithorum ordinariorum fere plana cum bulla
centrali vel microcrystallorum dorsa tenui instructa.
Coccolithi stomatales (laminolithi zygoformes) dorsa transversa acuminata, cum vel sine perforatione instructi.
Typus: Zygosphaera hellenica KAMPTNER (SD: LOEBLICH & TAPPAN
1963, p. 194).
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INA Newsletter vol.4 - 1982

Zygosphaera bannockii (BORSETTI & CATI) HEIMDAL n. comb.
Basionym: Sphaerocalyptra bannockii BORSETTI & CATI, 1976,
p. 212, pl. 13, figs. 4-6. Synonym: Laminolithus bannockii(BORSETTI & CATI) HEIMDAL, HEIMDAL & GAARDER 1980, p. 8,
pl. 2, fig. 18.
Zygosphaera hellenica KAMPTNER, 1937, p. 306, pl. 16,figs 27-29. Synonym: Laminolithus hellenicus (KAMPTNER)
HEIMDAL, HEIMDAL & GAARDER 1980, p. 8, pl. 3, figs 19-21.
Zygosphaera marsilii (BORSETTI & CATI) HEIMDAL n. comb.
Basionym: Sphaerocalyptra marsilii BORSETTI & CATI, 1976,
p. 212, pl. 13, figs 7-10. Synonyms: Corisphaera gracilis
KAMPTNER, BORSETTI & CATI 1976, p. 218, pl. 15, fig. 9;
C. aff. gracilis KAMPTNER, BORSETTI & CATI 1976, p. 218,
pl. 15, figs 10, 11; Laminolithus marsilii (BORSETTI & C~TI)
HEIMDAL, HEIMDAL & GAARDER 1980, p. 8, pl. 3, figs 22, 23;?Zygosphaera amoena KAMPTNER, 1937, p. 305, pl. 16, figs 24-26.
Calyptrolithina HEIMDAL n. gen.
DERIVATION OF NAME: Greek kalyptra, cap-shaped covering; Greeklithos, stone; referring to the calyptroform ordinary coccoliths.
Diagnosis
Coccolith case subspherical, dimorphic, with distinct flagellar
area. Ordinary coccoliths calyptroliths, proximal part consisting of a basal ring which bears a tube widening distally;
central part highly vaulted, surrounded at base by the distal
crystal rings of the tube. Proximal ring, tube and central
part formed by a single layer of microcrystals arranged in
the usual hexagonal pattern, second-crystal ring from distal
margin of tube with a regular row of holes, most easily seenin distal view. Stomatal coccoliths zygoliths with high,pointed bridge normal to long axis of coccolith.
Type: Calyptrolithina divergens (HALLDAL & MARKALI) HEIMDAL
n. comb.
INA Newsletter vol.4 - 198253

Testa coccolithica subsphaerica, dimorpha, area flagellari
distincta. Coccolithi ordinarii calyptrolithi, parte proximali
anulo fundi tubum se in exteriorem partem dilatantem ferente
constante; pars centralis alte convexa, in basi anulis tubi
crystallorum distantibus circumdata. Anulus proximalis, tubus
parsque centralis una microcrystallorum lamina ordine hexagonali usitato fermata consistunt, crystallorum anulo secundo
a margine tubi distante cum foraminum serie regulari, facillime
e distante visu. Coccolithi stomatales zygolithi cum pontealto acuminate axi longo coccolithico directo.
Typus: Calyptrolithina divergens (HALLDAL & MARKALI) HEIMDALn. comb.
Calyptrolithina divergens (HALLDAL & MARKALI) HEIMDAL n. comb.
Basionym: Zygosphaera divergens HALLDAL & MARKALI 1955, p. 8,pl. 2.
Calyptrolithina divergens f. tuberosa(HEIMDAL) HEIMDAL n. comb.
Basionym: Zygosphaera divergens HALLDAL & MARKALI f. tuberosa
HEIMDAL, HEIMDAL & GAARDER 1980, p. 12, pl. 3, fig. 25.

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INA Newsletter vol.4 - 1982

Table 1. Coccolith type in the holococcolithophorid genera studied in HEIMDAL & GAARDER {1980).
Genus/type species

Coccolithcase

Coccolithtype

Crystallolithus
c. hyalinus
Syracolithus
S. dalmat;i..cus
Zygosphaeraz. hellenica
Calyptrosphaera

Monomorphic

crystallolith

Monomorphic

Laminolith

D;i..morphic

Coccolith type
Stomatal coccoliths
Ordinary coccoliths

Laminolithzygoform laminolith

Dimorphic

Calyptrolith

Calyptrol;tth

Dimorphic

Calyptrolith

Calyptrolith

Dimorphic

Calyptrolith

zygolith

Dimorphic

Zygolith

Zygolith

gracilis
Helladosphaera

Dimorphic

Zygolith

Helladol;ith

H. cornifera
Periphyllophora

Monomorphic

Monomorphic

Calyptrolith~·

globosa
Sphaerocalyptra
quadridentata
Calyptrolithophora
C. papillifera~·

Calyptrolithina
c. divergens
Homozygosphaera
H. spinosa
CorisphaeraMonomorphic

Zygol;lth~·\Jl\Jl

P. mirabil;i..sHelladolith.

References
BORSETTI, A.M. & F. CATI (1976): Il nannoplancton calcareo
vivente nel Tirreno centro-meridionale, Parte 2. - Giorn.
Geol., Ser. 2a, 40:209-240.
HALLDAL, P. & J. MARKALI (1955): Electron microscope studies
on coccolithophorids from the Norwegian Sea, the Gulf
Stream and the Mediterranean. - Avh. norske Vidensk Akad.
I. Mat.-Nat. Kl. 1955, 1:1-30.
HEIMDAL, B.R. & K.R. GAARDER (1980): Coccolithophorids fromthe northern part of the eastern central Atlantic. I.
Holococcolithophorids. - "Meteor" Forsch.-Ergebn. D, No.
32:1-14.
KAMPTNER, E.

(1936): Dber die Coccolithineen der SUdwest-kUste von Istrien. - Anz. Akad. Wiss. Wien, 73:243-247.
(1937): Neue und bemerkenswerte Coccolithineen aus demMittelmeer. - Arch. Protistenk. 89:279-316.
LOEBLICH, A.R.

(Jr.) & H. TAPPAN (1963): Type fixation andvalidation of certain calcareous nannoplankton genera. Proc. Biol. Soc. Wash. 76:191-196.

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